Purpose
Spectral-domain optical coherence tomography (SD-OCT) using a split-spectrum amplitudinal decorrelational angiography (SSADA) algorithm allows for a novel way to assess retinal micro-circulation in 3D without using an intravenous contrast agent. Our study compares images of age-related macular degeneration (ARMD) with occult choroidal neovascularization (CNV) and retinal pigment epithelial detachment (RPED), and non-proliferative diabetic retinopathy (NPDR) with capillary nonperfusion using SSADA and fluorescein angiography (FA) to demonstrate the capabilities of this software.
Methods
FA imaging was obtained with an Ophthalmic Imaging Systems Winstation XP camera (Sacramento, CA). OCT images were obtained at 70 kHz A-scans per second using the Optovue Avanti RTVue XR OCT system (Fremont, CA). Prototype software using SSADA algorithms constructed SD-OCT angiography of the retinal microvasculature. The software then reconstructed the retinal and choroidal microvasculature in 3D, with the ability to isolate vasculature and circulation in individual layers of customized height in the retina and choroid.
Results
Imaging from SD-OCT angiography and FA were compared. In a patient with ARMD, SD-OCT angiography visualized the RPED and CNV well, especially the network of occult CNV. In a patient with NPDR, SD-OCT angiography demonstrated capillary non-perfusion better than FA.
Conclusions
SSADA provides detailed SD-OCT angiography of retinal pathology that shows promise of noninvasive angiography comparable with FA and a potentially deeper understanding of retinal and choroidal diseases.
Keywords: 552 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) •
688 retina •
550 imaging/image analysis: clinical